Therapeutic Hypothermia for Newborns with Hypoxic Ischemic Encephalopathy

Chang, Meayoung

Abstract

Brain injury secondary to hypoxia-ischemia (HI) is one of the major causes of neonatal death and severe, long-term neurologic deficits in children. Aside from hypothermia, no established therapies exist. Although the specific mechanisms of hypothermic neuroprotection remain unclear, in part hypothermia suppresses a broad range of injurious factors involved in the both early or primary and late or secondary phases of cell damage and death during the HI injury. In particular, latent (early recovery) phase-a brief period of normal cerebral energetics between resuscitation/reperfusion and the secondary phase of impaired energy metabolism and injury - represents the effective window of opportunity for initiation of therapeutic hypothermia, and ameliorate the later secondary energetic decline, neuronal death and the subsequent neurodevelopmental disability. Randomized controlled studies and systemic reviews have demonstrated that moderate hypothermia (33-35degrees C of core body temperature) using systemic or whole body cooling and selective head cooling, started within 6 hours after birth and protracted for 72 hours, significantly improves survival and reduces neurologic impairment in term and near-term infants with moderate and severe HI encephalopathy. Throughout the world, therapeutic hypothermia is increasingly recommended and we should have the protocols, equipment and training to treat the newborns with moderate and severe HI encephalopathy with therapeutic hypothermia.